Troubleshooting An Abr - HP ProCurve Secure Router 7203 dl Advanced Management And Configuration Manual

IP Routing—Configuring RIP, OSPF, BGP, and PBR
Troubleshooting Routing
13-160
7. If the router has established full adjacency with its neighbors, but it still
lacks routes to destinations in the area, other routers may be the source
of the problem. Troubleshoot these routers as you would a router not
sending the correct routes. (See "The Router Is Not Sending the Correct
Routes" on page 13-160.)
8. An internal router should also receive IA routes so that it can forward
inter-area traffic. Several problems with inter-area routing can arise:
• The area was configured to not receive route summaries on the local
router—Enter show running-config and look for an area <area
ID> stub no-summary setting.
• An ABR incorrectly classifies the local area as a total stub area.
• The ABR does not generate route summaries or generates them
incorrectly—In this case, the router might have a route for inter-area
traffic, but the traffic is misrouted when it reaches area 0.
If the router has received a default route but no inter-area route summa-
ries, it has probably been defined as a total stub area on either the local
router or its ABR. Enter area <area ID> stub without the no-summary
option from the OSPF configuration mode context to solve the problem
on a local router. If the problem seems to be on the ABR's end, use the
tips for troubleshooting an ABR. (See "Troubleshooting an ABR" on page
13-160.)
The Router Is Not Sending the Correct Routes. View the OSPF inter-
faces (show ip ospf int). It is possible that OSPF has not been enabled on
the correct networks in the correct area. Troubleshoot as described above in
steps 3 through 6.
Sometimes a router has interfaces that should not run OSPF, but which make
connections that OSPF routers should take into account when generating a
network topology. In this case, you should redistribute connected routes into
OSPF. (See "Redistributing Routes Discovered by Other Protocols (ASBRs)"
on page 13-55.)

Troubleshooting an ABR

An ABR should be able to route traffic it receives from a stub area through the
network backbone to the destination area. It should also be able to route intra-
area traffic in area 0.
If the ABR is only routing intra-area traffic incorrectly, troubleshoot it as you
would an internal router.